UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

 

Washington, DC 20549

 

FORM 8-K

 

CURRENT REPORT

 

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

 

Date of Report (Date of earliest event reported): December 21, 2007

 

Callisto Pharmaceuticals, Inc.

(Exact name of registrant as specified in its charter)

 

Delaware

 

001-32325

 

13-3894575

(State or other jurisdiction

 

(Commission

 

IRS Employer

of incorporation or organization)

 

File Number)

 

Identification No.)

 

420 Lexington Avenue, Suite 1609

New York, New York  10170

(Address of principal executive offices)

 

Registrant’s telephone number, including area code: (212) 297-0010

 

 

(Former name or former address, if changed since last report)

 

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

 

o  Written communication pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

 

o  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

 

o  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

 

o  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

 

 

 


 

Item 7.01.              Regulation FD Disclosure

 

On December 21, 2007, Callisto Pharmaceuticals, Inc. (the “Company”) mailed a letter to its stockholders from Gary S. Jacob, its Chief Executive Officer. A copy of the stockholder letter is filed as Exhibit 99.1 hereto.

 

Item 9.01.              Financial Statements and Exhibits

 

(d)         Exhibits.

 

99.1                           Letter to stockholders of Callisto Pharmaceuticals, Inc.

 

The information in this Form 8-K and the Exhibit attached hereto shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, except as shall be expressly set forth by specific reference in such filing.

 

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SIGNATURE

 

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

 

Dated:    December 21, 2007

 

 

 

CALLISTO PHARMACEUTICALS, INC.

 

 

 

By:

/s/ Gary S. Jacob

 

 

 

Gary S. Jacob, Ph.D.

 

Chief Executive Officer

 

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